JPS5959440A - Composite barriering film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION More specifically, the present invention relates to a composite barrier film with excellent weather resistance, which is formed by providing a cured coating film of a specific fluorine-containing copolymer on a saponified ethylene-vinyl acetate copolymer film. be.

Saponified ethylene-vinyl acetate copolymer films have excellent gas barrier properties and have been widely used in food packaging and other applications. However, this film has poor weather resistance and cannot be applied as a membrane material in outdoor applications such as balloons and air membrane structures.

The present inventors have conducted intensive research based on the recognition of the above problems, and have found that by providing a cured coating film of a specific fluorine-containing copolymer on the film, weather resistance is significantly improved. ,
It has been found that a composite barrier membrane can be obtained which is also applicable to outdoor applications.

Thus, the present invention has been completed based on the above findings RTC, and includes a monomer containing trophic sites based on tetrafluoroethylene and alkyl vinyl ether as main components and further providing reactive sites on a saponified ethylene-vinyl acetate copolymer film. The present invention provides a novel composite barrier film comprising a cured coating film of a fluorine-containing copolymer containing units based on polymers in a proportion of 20 moles or less.

In the present invention, various ethylene/vinyl acetate copolymer compositions or saponification degrees of ethylene/vinyl acetate can be used as the combined saponified film, but from the viewpoint of gas barrier properties, Those with a relatively high vinyl acetate content and a high degree of saponification can be used in IT applications. The thickness of the film is appropriately selected depending on the application, but is usually 5 to 100 μm, preferably υ, [1
0~60μ? 1. In the present invention, the above film is based on tetrafluoroethylene and alkyl vinyl ether <-rc
It is important to provide a cured coating of a fluorine-containing violet copolymer containing units based on monomers that serve as production moieties and that further serve as reaction sites in a proportion of 20 molar or less. Such a coating film has excellent not only weather resistance but also flexibility, making it possible to create a highly durable composite film.

Here, the content ratio of units based on te)-lafluoroethylene and alkyl vinyl ether in the fluorine-containing copolymer is rat: weather resistance, solubility.

From the viewpoint of flexibility, etc., a range of about 70:3 level 0 near 0 can be preferably adopted. As a 4ft alkyl vinyl needle component, 1) from the viewpoint of strength, polymerization characteristics and OJ coating film properties, C) does not contain a linear, monobranched or cyclic alkyl group having about 2 to 8 carbon atoms. things are exemplified,
The component may contain units based on two or more alkyl vinyl ethers. In such copolymers, functional group-containing vinyl ethers such as hydroxyalkyl vinyl needles and U-grindyl vinyl ethers are preferably employed as the comonomers that can occupy reactive sites due to their copolymerization characteristics. It is.

The reaction sites in the copolymer are exposed to a single copolymer.
) The content ratio of Cj is 20 molt or less, preferably Cj1~
It is about 15 molar. If the ratio is too small,
1. If the curing becomes insufficient and the dog is scratched too much. Both methods are inconvenient because the flexibility of the coating film is impaired. In addition to these essential di-components, other concomitant components 1iC
It is also possible to use hexacopolymers modified by containing, for example, 15 molar units or less of the base units.

The above copolymer can be produced by adding a monomer mixture of a predetermined proportion to a polymerization medium or coexisting with υj: 11.

In the present invention, the formation of a fluorine-containing copolymer cured coating film f
It is possible to implement FiJ using the following methods, but from the viewpoint of operability,
A curing agent such as a polyfunctional compound having reactivity with the reaction site of the copolymer is added to a solution containing a fluorine-containing rigged car body dissolved in an organic solvent in an amount of 1 to 100 parts by weight per 100 parts by weight of the copolymer.
A coating composition is prepared by containing the film in an amount of about 0.5 to 50 M parts by weight, and the composition is applied onto the film by various methods to observe the volatilization of the solvent and the formation of the coating film. A method of curing can be adopted in a freeze-friendly manner. A curing aid or a U curing catalyst may be appropriately added to the composition.

In such a method, for a fluorine-containing polymer whose reactive site is a hydroxyl group, polyvalent incyanate or titanium alkoxide is preferably used as a curing agent if the composition is to be cured at room temperature. . When the composition is made into a heat-curing type, melamine curing agents, urea resin curing agents, polybasic acid curing agents, etc., which are used in ordinary heat-curing paints (IJ), are used. As a hardening agent.

It is valid. Here, examples of melamine curing agents include Shima, methylated melamine, methylated melamine, and epoxy-stiff melamine.
No. 11 modification 4 is suitable for use, and the degree of self-condensation can be selected as appropriate. Examples of urea oil include methylated urea and butylated urea. Useful polybasic acid curing agents include long-chain aliphatic polycylindrical carboxylic acids, aromatic polyhydric A-carbon acids or their anhydrides, and block polyvalent ino-7anates. By adding d1 acidic catalyst when using melamine or tJ urea hardening agent.
As another example, in the case of fluorine-containing polymer's reactive site/vaejo group, amines, carbonic acid gradients, phenols, and alcohols can be used to accelerate curing. In this case, multi-human IJ
Oxygen compound! Non-aromatic diols are useful as curing aids in l″r.

The thickness of the cured coating film of the fluorine-containing copolymer thus obtained is usually 5 to 60 μm. L-<1d10-3
It is appropriately selected from the range of 0 μm.

In the present invention, various components such as an ultraviolet absorber 1 colorant and a water repellent material are added to the cured coating film to provide various properties such as durability, aesthetics, and water repellency. Improvements are also possible. Of course, it is also possible to increase the mechanical strength by layering a fiber phase on the opposite side (1110) to the coated side.

The bonded barrier film of the present invention has excellent weather resistance, and is also advantageous in terms of lightness because the film and the cured coating are bonded tightly even through an adhesive.
It is extremely useful as an outdoor membrane material such as air membrane structures.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Using a fluorine-containing copolymer containing mono(t7) based on tetrafluoroethylene, ethyl hinyl ether, and hydroquine butyl hinyl ether in a proportion of 50 mol%, 40 mol%, and 10 mol%, respectively, Prepare the following coating composition.

Fluorine-containing copolymer 100 parts by weight Insiaput curing agent (manufactured by Sumitomo Bayer Urethane: TEIS module J1o loss part dibutyltin silaurylate 0.0031 (d), 'NII mixed solvent 200 parts by weight 2, mixed solvent is methyl in butyl coolant.

It is a mixture of quince, ethyl acetate and cellosolve acetate in a weight ratio of 1:1:1:0.5.

The resulting coating composition was applied onto a commercially available saponified ethylene-vinyl acetate copolymer film (thickness 15 μm; manufactured by Kuraray: EVAL, -F) until the dry film thickness was 20 μm.
The coating was spray-painted to give a cured coating, and the coating was left to stand at room temperature for 7 days to cure the coating, thereby obtaining a composite barrier film having a cured coating.

The thus obtained composite barrier membrane has a sphere diameter of 1%'',
In the DuPont impact test with a load of 15001i' and a falling height of 50L:rn, it exhibited adhesion without causing damage and exhibited excellent gas barrier properties. Even after an accelerated weathering test of 4 Qυ hours, the tensile strength and elongation corresponding to the initial values of 90 modulus and 40 modulus were still maintained.

In contrast to this, -C', the Chinese and German saponified ethylene-vinyl acetate copolymer films without the above-mentioned cured coating showed a 100-hour test result when subjected to accelerated weathering tests using a similar Dusai Kruzer meter. The tensile strength and elongation of the film decreased to almost zero.

Example 2 50 moles each of units based on tetrafluoroethylene, hequin rubinyl ether, inbutyl vinyl needle and hydroxybutyl vinyl ether,
The following coating compositions were prepared using fluorine-containing copolymers containing 25 mol, 20 mol, and 5 mol.

Fluorine-containing copolymer 100 parts by weight Titanium oxide (manufactured by Ishikata Sangyo: CR-913) 50 n Mixed solvent 150 #Melamine resin (manufactured by Mitsui Toatsu - Riimel 325'+ 8 7 Same curing catalyst (manufactured by Mitsui Toatsu) : Catalys l-6000) 0.05
rr4 Mixed solvent with alcohol, butanol, ethyl chloride, and high boiling point aromatic solvent (manufactured by Tonen: Norvesoso 15 D)'z weight, E ratio of 1:1
:1:5 ratio.

The coating composition described in Example 2 was applied onto the same film as in Example 1 using a roll coater so that the dry film thickness was 20μ7F+, and was baked and cured at 120C for 40 minutes for 1J.

After a 400-hour accelerated weathering test using a dew cycle weather meter, the tensile strength and elongation retention of the thus obtained composite barrier film were both 100 cm. Furthermore, no damage such as cracking was observed in the composite film even after O'R bending was repeated 10 times.

Example 3 <-rp position of tetrafluoroethylene, cyclohexyl vinyl needle, glycidyl vinyl ether and ethyl vinyl ether, respectively i+-50 molar ratio, 25
The following coating composition was prepared using a fluorine-containing rigging composition containing fluorine-containing material in the proportions of mol, 8 mol, and 17 mol.

Fluorine-containing copolymer 100 double leaf part intermediary solvent 150 trimellitic anhydride
12 Ultraviolet absorber (Kyodo Yakuhin: Viosorb-130) To
)7+-ethylpendylammonium chloride 'J)'
If using the above composition, baking was carried out at 100°C
A sacrificial film was obtained in the same manner as in Example 2 except that the heating time was 2 hours.

After a 200-hour accelerated weathering test using a dew cycle weather meter, the composite film V↓ obtained by force-combing had tensile strength and elongation equivalent to 85% and 50% of the initial values.

Claims (1)

[Claims] On the saponified ethylene-vinyl acetate copolymer film,
A cured coating film of a fluorine-containing copolymer containing units based on tetrafluoroethylene and O-alkyl vinyl ether as a main component and further containing units based on a monomer providing a reactive site in a proportion of 20 mol or less is provided. A composite barrier membrane characterized by: